package com.hmdp.service.impl;


import cn.hutool.core.bean.BeanUtil;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.hmdp.dto.Result;
import com.hmdp.entity.VoucherOrder;
import com.hmdp.mapper.VoucherOrderMapper;
import com.hmdp.service.ISeckillVoucherService;
import com.hmdp.service.IVoucherOrderService;
import com.hmdp.utils.RedisWorker;
import com.hmdp.utils.UserHolder;
import lombok.extern.slf4j.Slf4j;
import org.redisson.api.RLock;
import org.redisson.api.RedissonClient;
import org.springframework.aop.framework.AopContext;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.core.io.ClassPathResource;
import org.springframework.data.redis.connection.stream.*;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.data.redis.core.script.DefaultRedisScript;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import javax.annotation.PostConstruct;
import java.time.Duration;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

/**
 * <p>
 * 服务实现类
 * </p>
 *
 * @author 虎哥
 * @since 2021-12-22
 */
@Service
@Slf4j
public class VoucherOrderServiceImpl extends ServiceImpl<VoucherOrderMapper, VoucherOrder> implements IVoucherOrderService {

    @Autowired
    private ISeckillVoucherService seckillVoucherService;
    @Autowired
    private RedisWorker redisWorker;

    @Autowired
    private StringRedisTemplate stringRedisTemplate;

    @Autowired
    private RedissonClient redissonClient;

    private  static final DefaultRedisScript<Long> SECKILL_SCRIPT;
    static {
        SECKILL_SCRIPT =new DefaultRedisScript<>();
        SECKILL_SCRIPT.setLocation(new ClassPathResource("seckill.lua"));
        SECKILL_SCRIPT.setResultType(Long.class);
    }

    private IVoucherOrderService proxy;

    private static final ExecutorService SECKILL_ORDER_EXECUTOR = Executors.newSingleThreadExecutor();
    @PostConstruct
    private void init(){
        SECKILL_ORDER_EXECUTOR.submit(new VoucherOrderHandler());
    }


    public void handleVoucherOrder(VoucherOrder voucherOrder){
        Long userId = voucherOrder.getUserId();
        RLock lock = redissonClient.getLock("lock:order:" + userId);

        boolean isLock = lock.tryLock();
        if (!isLock) {
            log.error("不允许重复下单");
            return;
        }

        try {
            proxy.CreateVoucherOrder(voucherOrder);
        } finally {
            lock.unlock();
        }
    }
    @Override
    public Result seckillVoucher(Long voucherId) {
        Long userId = UserHolder.getUser().getId();
        long orderId = redisWorker.nextId("order");

        Long result = stringRedisTemplate.execute(
                SECKILL_SCRIPT,
                Collections.emptyList(),
                voucherId.toString(), userId.toString(),String.valueOf(orderId)
        );
        int r = result.intValue();
        if(r!=0){
            return Result.fail(r == 1? "库存不足":"不能重复下单");
        }

        


        proxy =(IVoucherOrderService) AopContext.currentProxy();


        return Result.ok(orderId);

    }

   /*阻塞队列
       private BlockingQueue<VoucherOrder> orderTasks = new ArrayBlockingQueue<>(1024*1024);
    @Override
    public Result seckillVoucher(Long voucherId) {
        Long userId = UserHolder.getUser().getId();

        Long result = stringRedisTemplate.execute(
                SECKILL_SCRIPT,
                Collections.emptyList(),
                voucherId.toString(), userId.toString()
        );
        int r = result.intValue();
        if(r!=0){
            return Result.fail(r == 1? "库存不足":"不能重复下单");
        }

        long orderId = redisWorker.nextId("order");
        VoucherOrder voucherOrder = new VoucherOrder();

        voucherOrder.setId(orderId);


        voucherOrder.setVoucherId(voucherId);
        voucherOrder.setUserId(userId);

        orderTasks.add(voucherOrder);

        proxy =(IVoucherOrderService) AopContext.currentProxy();


        return Result.ok(orderId);

    }*/

    /*@Override
    public Result seckillVoucher(Long voucherId) {
        SeckillVoucher voucher = seckillVoucherService.getById(voucherId);

        if (voucher.getBeginTime().isAfter(LocalDateTime.now())) {
            return Result.fail("秒杀尚未开始！");
        }

        if (voucher.getEndTime().isBefore(LocalDateTime.now())) {
            return Result.fail("秒杀已经结束！");
        }

        if (voucher.getStock() < 1) {
            return Result.fail("库存不足");
        }
        Long userId = UserHolder.getUser().getId();
//        SimpleRedisLock lock = new SimpleRedisLock("order:" + userId, stringRedisTemplate);
        RLock lock = redissonClient.getLock("lock:order:" + userId);

        boolean isLock = lock.tryLock();
        if (!isLock) {
            return Result.fail("不允许重复下单");
        }

        try {
            IVoucherOrderService proxy = (IVoucherOrderService) AopContext.currentProxy();
            return proxy.CreateVoucherOrder(voucherId);
        } finally {
            lock.unlock();
        }

    }*/

    @Transactional
    public void CreateVoucherOrder(VoucherOrder voucherOrder) {
        Long userId = voucherOrder.getUserId();
        Long voucherId = voucherOrder.getVoucherId();

        Integer count = query().eq("user_id", userId).eq("voucher_id", voucherId).count();
        if (count > 0) {
            log.error("用户已经购买过一次！");
        }
        boolean success = seckillVoucherService.update()
                .setSql("stock=stock-1")
                .eq("voucher_id", voucherId).gt("stock", 0).update();
        if (!success) {
            log.error("库存不足！");
            return;
        }


        save(voucherOrder);



    }

    private class VoucherOrderHandler implements Runnable {
        private String queueName = "stream.orders";
        @Override
        public void run() {
            while (true){
                try {
                    List<MapRecord<String, Object, Object>> list = stringRedisTemplate.opsForStream().read(
                            Consumer.from("g1", "c1"),
                            StreamReadOptions.empty().count(1).block(Duration.ofSeconds(2)),
                            StreamOffset.create(queueName, ReadOffset.lastConsumed())
                    );
                    if(list==null||list.isEmpty()){
                        continue;
                    }
                    MapRecord<String, Object, Object> mapRecord = list.get(0);
                    Map<Object, Object> values = mapRecord.getValue();
                    VoucherOrder voucherOrder = BeanUtil.fillBeanWithMap(values, new VoucherOrder(), true);

                    handleVoucherOrder(voucherOrder);
                    stringRedisTemplate.opsForStream().acknowledge(queueName,"g1",mapRecord.getId());
                } catch (Exception e) {
                    log.error("处理订单异常",e);
                    handlePendinglist();
                }

            }
        }

        private void handlePendinglist() {
            while (true){
                try {
                    List<MapRecord<String, Object, Object>> list = stringRedisTemplate.opsForStream().read(
                            Consumer.from("g1", "c1"),
                            StreamReadOptions.empty().count(1),
                            StreamOffset.create(queueName, ReadOffset.from("0"))
                    );
                    if(list==null||list.isEmpty()){
                        break;
                    }
                    MapRecord<String, Object, Object> mapRecord = list.get(0);
                    Map<Object, Object> values = mapRecord.getValue();
                    VoucherOrder voucherOrder = BeanUtil.fillBeanWithMap(values, new VoucherOrder(), true);

                    handleVoucherOrder(voucherOrder);
                    stringRedisTemplate.opsForStream().acknowledge(queueName,"g1",mapRecord.getId());
                } catch (Exception e) {
                    log.error("处理订单异常",e);
                }

            }
        }
    }
}
